3D holography is technology for realizing 3D images that can be viewed in all directions of 360 degrees and 3D stereoscopic images generated through 3D holography have advantages of providing 3D effects to enhance reality and immersion. Holography includes real 3D holography provides 3D images that can be viewed in all directions of 360 degrees and pseudo-holography that projects a 2D image onto a plane rather than providing a perfect 3D stereoscopic image. A typical example of a pseudo-hologram is a floating hologram. In addition, various types of pseudo-holography are being commercialized or studied.